1. Field of the Invention
This invention relates to charge-coupled devices for metering charge and, more particularly, to a circuit for metering electrical charge for forming a signal indicative of a function of input signals to said circuit.
2. Description of the Prior Art
Matrix multiplication of analog signals and, in particular, analog signal correlation, for example, has been performed by such techniques as converting the analog signals to digital signals and performing digital multiplication or correlation. However, such A/D conversion techniques require large amounts of hardware which uses relatively large amounts of space and decreases system reliability.
It is desirable, therefore, to devise a method and apparatus for analog signal matrix multiplication or correlation which does not include A/D conversion.
However, the technology disclosed in the above application Ser. No. 842,834, a hybrid U.S. Pat. No. 4,156,923 combination of discrete components such as capacitors and transistors. An integrated, monolithic device is needed so that it can be fabricated at the same time and on the same chip as the charge transfer devices that perform the signal correlation. Also, spurious effects due to parasitic capacitances such as noise pickup causes degraded performance.